Belt-drive log-turning nigger



March 11, 1952 E. G. LETOURNEAU 2,588,735

BELT-DRIVE LOG-TURNING NIGGER Filed May 16, 1950 s SheetsSheet 1 w INVENTOR March 11, 1952 E. cs. LETOURNEAU 2,588,735

BELT-DRIVE LOG-TURNING NIGGER Filed May 16, 1950 3 Sheets-Sheet 3 INVENTOR Patented Mar. 11, 1952 BELT-DRIVE LOG-TURNING NIGGER Emile Gedeoin Letourneau, Winfield, Alberta, Canada Application May 16, 1950, Serial No. 162,207 In Canada May 17, 1949 4 Claims.

The invention herein relates to nigger bars as used in sawmill operations for turning and holding logs while cutting fiitches therefrom.

The primary object of the invention herein is to provide a .nigger that can be used in small mills driven by electric or gasoline power.

An additional object is to provide a device of this character that can be easily transported to the desired location. A further object is to provide a nigger whose installation requirements will not be prohibitive, either in size or in cost, to the operator of a small mill.

A still further object is to provide a nigger that can be quickly and simply installed in a minimum of time.

A still further object is to provide a nigger that can be used with the majority of the present-day sawmill equipment with little or no alteration.

Other objects and advantages will become apparent from a perusal of the following specification read in the light of the attached drawings, it being understood that the preferred embodiment herein set forth is by way of illustration and example only, and is not to be taken as a limitation. The invention herein is to be limited only by the terms of the appended claims and by the prior art. In the drawings,

Figure 1 is a side elevational view of the device partially broken away to illustrate more clearly the belt drive and the belt tightening pulleys.

Figure 2 is a sectional view of the nigger bar partially broken away to illustrate the hoisting pulley and its hoisting chain.

Figure 3 is a sectional view of the uppermost portion of the nigger bar partially broken away .to illustrate its log-engaging teeth.

Figure 4 is aplan view of the device taken along the line A-A of Fig. 1.

Figure 5 is an end view of the mechanism above the sawmill floor.

Figure 6 is a broken-away isometric view of the igger bar shock absorbing mechanisms.

' Figure -7 is an enlarged front view of the nigger hoisting pulley and the hoisting chains.

The device consists of a lower framework comprising a pair of longitudinal members I, I supported on a pair of lateral members '2, 2 and an upper framework comprising a similar pair of longitudinal members 3, 3 supported on a pair of lateral members 4, 4. The upper framework is supported above the lower framework in paral- ;;lel alignment therewith by the vertical tubular ".mfimbers 5, 5., 5, 5.

The above described framework is positioned immediately below the sawmill floor 44 in order that the interspaced log-engaging teeth 68 on the nigger l8 will engage with a log on the sawmill carriage. The sawmill carriage may be any of the common types in use at the present time in conjunction with steam or hydraulically operated niggers. This feature has therefore been omitted from the drawings in the interest of simplicity.

The nigger bar guide 6?, (ii is composed of two parallel right-angle plates firmly fixed to the sawmill floor 64 and is adapted to check any lateral movement of the nigger bar- H3. Automatic adjustment of the nigger bar It to logs of various circumference is provided by the longitudinal opening between the nigger bar guides 61, 61. A shock absorbing bar l5 tensionably mounted in supports 13, 73 by the rods H, H, tension spring 12, 12 and collars i8 is provided to absorb the force of the nigger bar returning to its normal vertical position. The collars l6, 18 are fixed adjustably on the rods H, H between the supports l3, '13 to bear against the ends of the tension springs l2, 12 when the bar 15 and the rods 1 l, H are moved forwardly. The collars 16, 16 may be adjusted slidably along the rods H, H to adjust the tension of the springs 72, 12.

The mechanism for vertically elevating the nigger bar in 10g turning operations is controlled by the lever 43 pivotally mounted at 45 in the lever mount 46 while the mechanism for holding the nigger bar against the log is controlled by the foot pedal 63 mounted on the foot pedal shaft 62.

With reference now to the mechanism below the sawmill floor, which actuates the nigger bar:

The lateral parallel shafts 6, l and 8 are journalled in pillow blocks fastened to the lower longitudinal members i, l. Fixed at one end of the shaft 1 outside the lower framework is the main drive pulley 9, Fig. 4, driven in a counterclockwise direction by the main drive belt l0 coupled to a suitable power source. The main drive pulley 9 and the main drive belt 10 have, in the interests of simplicity, been omitted from Figure l in the drawings. Also fixed on the shaft 1 inside the lower framework are secondary drive pulleys H and I2.

A driven pulley i3 is fixed on the shaft in longitudinal alignment with the secondary drive pulley [2. The belt I4 is adapted to couple loosely the said pulleys l2 and I3.

The driven pulley I5 is fixed on the shaft 3 in longitudinal alignment with the secondary,

3 loosely the said pulleys H and I5. Also fixed on the shaft 8 is the nigger pulley Fig. 2. The friction pulley 24 is fixed in co-operative longitudinal alignment with the nigger pulley H on the shaft 6.

The co-operative relationship and alignment of the above pulleys will be seen more clearly on reference to Figure 4 in the drawings.

The nigger bar is composed of the nigger shaft |8 having, as is common in a device of this sort, interspaced log-engaging teeth 68. The preferred construction of the nigger bar and the interspaced log-engaging teeth will be seen clearly on reference to Figure 3. The construction illustrated being only one practical example thereof since a variety of systems could be used that would allow the log-engaging teeth to grip and turn a log on the upward strip of the nigger and on the downward stroke of the nigger would swing inwardly toward the nigger bar and bypass the log. The nigger shaft I8 is vertically rigidly mounted on a plurality of vertical, parallel, right-angled members 20, 20, 20, 29 which are in turn rigidly affixed to, and so spaced on, the base plate l9 as to slidably fit laterally over the shaft 8 and longitudinally over the nigger pulley I. The solid rubber shock absorbers 14, 14 are suitably fixed in the lateral openings between the members 20, 20, 20, above the shaft 8 and the nigger pulley I! to absorb the shock and check the downward travel of the nigger bar at the required position.

Elevation of the nigger bar for log turning purposes is accomplished by the chain 2| winding on the nigger pulley I! in the form of a winch. The

chain 2| extends vertically, parallel to the nigger bar, with one end fixedly attached to the base plate l9, around the nigger pulley l1 and has its opposite end connected to a point on the periphery of the nigger pulley II. A second chain 22 also has one of its ends connected to a point on the periphery of the nigger pulley I1 and has the other of its ends connected through the tension spring 23 to an extruding lug 69 midway on the nigger shaft 8, see Figures 7 and 2. The tension spring 23 serves ,to check the rotation of the nigger pulley when the nigger bar has terminated its downward travel.

The mechanism holding the nigger bar against a log on the sawmill carriage consists of a transmission rope 26 wound on the friction pulley 24 and connected by one of its ends through the chain 2'! to the extruding lug 28 on the nigger bar and by the other of its ends through the tension spring to one of the lateral upper members 4.

In order that the secondary drive pulley may, through the belt l6, actuate the driven pulley I5, the belt [6 is tightened into frictional engagement with the pulleys by elevating the belt tightening pulley 29. The belt tightening pulley 29 is positioned below the belt l6 and rotatably fitted on the shaft 39 between the parallel supporting beams 3|, 3| at one end thereof. The opposite ends of the supporting beams 3|, 3| are pivotally connected to the shaft 8 on opposite sides of the driven pulley IS. The belt tightening pulley is raised to engage the belt l6 by the lever 43, actuating the linkage composed of the com necting rod 4| pivotally connected at one end to the lower end 42 of the lever 43 and the opposite end to the upper end 49 of the lever 39. The lever 39 is fixedly attached at its opposite end to the lateral shaft 31 which is in turn rotatably journalled to the shafts 5, T and B, in shaft hangers 38 fastened to the upper longitudinal members A link 36 is also fixedly attached as to one of its ends to the lateral shaft 31' and pivotally connected by the other of its ends to the mid point 35 of the inverted U-shaped member 34. .The member 34 is fixedly attached by its ends to the lateral shaft 33 rotatably journalled in and between lugs 32, 32 extrudin from the supporting beams 3|, 3|.

The secondary drive pulley l2 similarly actu ates the driven pulley |3 when the belt tightening pulley "i1 is lowered to tighten the belt |4 into frictional engagement. The belt tightening pulley 41 is positioned above the belt l4 and is rotatably journalled on the shaft 48 between the parallel supporting beams 49, 49 at one end thereof. The parallel supporting-beams 49, 49 are pivotally connected to the shaft 6 on opposite sides of the driven pulley l3 in a similar manner to the parallel supporting beams 3|, 3|. The belt tightening pulley 41 is lowered to engage the belt |4 by depressing the foot pedal 53 which causes the foot pedal shaft 62 to actuate a linkage.

This linkage is composed of the bell crank 69 pivoted at 6| to one of the longitudinal members 3 and pivotally connected as to one of its arms to the lower end of the foot pedal shaft 62 and as to theother of its arms at 59 to one end of the connecting rod 53. The opposite end of the connecting rod 58 is pivotally connected at 51 to one end of thelink 56. The link 56 is fixedly connected at the other of its ends to the lateral shaft 55 which shaft is rotatably journalled parallel to the aforesaid shaft 31 in shaft hangers similar to the shaft hangers 38. The link 54 is also fixedly attached as to one of its ends to the lateral shaft 55 and pivotally connected as to the other of its ends to the mid point 53 of the inverted U-shaped member 52. The member 52 is fixedly attached by its ends to the lateral shaft 5 I, which shaft is rotatably journalled in and between the lugs 59, 50 extruding from supporting beams 49, 49.

It will therefore be seen readily that the belt tightening pulleys 4'! and 29, together with their co-operating linkages, act in the form of two clutches, frictionably engaging the belts l4 and H; with their respective pulleys. The belt tightening pulley 41 is maintained in an elevated inoperative position by the tension spring 65 firmly affixed as to one of its ends to one of the upper lateral members 4 and connected as to the other of its ends through the cable 66 to the lateral shaft 5|. The belt tightening pulley 29 is maintained in a lowered inoperative position by the weight of the pulley.

What I claim as my invention is:

l. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework operatively positioned below the sawmill floor; three lateral parallel shafts rotatably journalled in pillow blocks affixed to the said framework; a main drive pulley fixed outside the said framework to the center shaft of the three lateral parallel shafts, said main drive pulley coupled to a suitable power source; secondary drive pulleys fixed, inside the said framework, to the said center shaft; a driven pulley fixed, inside the said framework and in longitudinal alignment with one of the said secondary drive pulleys, to the second of the said three parallel shafts, such secondary drive pulley and driven pulley loosely coupled by a belt; a nigger bar having interspaced log-engaging teeth, vertically operable through thesawmill floor and adapted at its lower end to slidably fit laterally over the said second shaft and longitudinally over a hoisting pulley aflixed to the said second shaft; shock absorbing means mounted on the said nigger bar between the said nigger bar and the said second shaft; a chain fixed by one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends to the lower end of the said nig r bar; a second chain fixedby one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends through a tension spring to a lug extruding from the said nigger bar; a driven pulley, fixed inside the said framework and in longitudinal alignment with the other of the said secondary drive pulleys to the third of the three parallel shafts, such pulleys loosely coupled by a belt; a friction pulley fixed, inside the said framework and in longitudinal alignment with the said nigger bar, to the said third shaft; a friction cable wound on the said friction pulley, such cable coupled by one of its ends through a chain to the said nigger bar and by the other of its ends through a tension spring to the said framework; a belt tightening pulley rotatably journalled betweeen parallel supporting beams, at one end thereof, the opposite ends of the said supporting beams pivotally connected to the said second lateral shaft at each sideof the said driven pulley thereon; means for raising the said belt tightening pulley consisting of a U-shaped member pivotally connected by its ends to the said parallel beams and pivotally connected at its mid-point to one end of a lever, which is fixedly connected by the other of its ends to a lateral shaft; a second lever fixedly connected by one of its ends to the said lateral shaft and pivotally connected at the other of its ends to one end of a connecting rod which is pivotally connected by its other end to theslower end of an operating lever, the said operating lever extending vertically through the sawmill floor and pivotally supported at its mid-point in a suitable lever mount positioned to the sawmill floor; a second belt tightening pulley rotatably journalled between parallel supporting beams and at one end thereof, the opposite end of said beams being pivotally connected to the said third lateral shaft at each side of the said driven pulley thereon; means for lowering the said belt tightening pulley consisting of a U-shaped member pivotally connected by its ends to the said parallel beams and at its mid-point to one end of a lever which is fixedly connected by the other of its ends to a lateral shaft; a second lever fixedly connected by one of its ends to the said lateral shaft and pivotally connected by the other of its ends to one end of a connecting rod, the other end of the said connecting rod being pivotally connected to one arm of a bell crank the other arm of which is pivotally connected to a vertically operable shaft, said shaft extending vertically through the sawmill fioor; means for maintaining said second belt tightening pulley in a raised inoperative position consisting of a cable attached by one of its ends to the parallel supporting beams and at the other of its ends to a tension spring affixed to the said supporting framework; vertical guide members afiixed to the sawmill floor, longitudinally parallel on each side of the said nigger bar; shock absorbing means mounted on the said parallel members.

2. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework; lateral parallel shafts rotatably afiixed to the said framework;

. 6 a main drive pulley and secondary drive pulleys afiixed to one of the said shafts; a driven pulley fixed in longitudinal alignment with one of the said secondary drive pulleys to another of the said shafts and loosely coupled to the said secondary drive pulley by a, belt; a vertically .operable nigger bar adapted to slidably fit laterally over the last mentioned shaft and longitudinally over the hoisting pulley afiixed to the said shaft; shock absorbing means mounted on the said nigger bar between the said nigger bar and the said shaft; a chain fixed by one of its ends to a point on the periphery of the said hoisting pulley and by the other of its ends to the lower end of the said nigger bar; means for limiting the rotation of the said hoisting pulley during the downward travel of the said nigger bar; a second driven pulley fixed, in longitudinal alignment with another of the said secondary drive pulleys, to another of the said lateral parallel shafts and loosely coupled to the said secondary drive pulley by a belt; a friction pulley fixed to the last mentioned shaft in longitudinal alignment with the said nigger bar; means associated with the said friction pulley, connected to the said nigger bar and adapted to maintain pressure of the said nigger bar against a log positioned on the sawmill carriage; means for tightening the said loosely coupled belts singly or in unison, to engage said secondary drive pulleys and said driven pulleys, said belt tightening means operated and controlled from a preferred location on the sawmill floor; means for restricting lateral movement of the said nigger bar and guiding the said nigger bar during longitudinal oscillation; shock absorbing means mounted on the last mentioned means.

,3. A machine for turning and holding logs on their carriage during sawmill operations comprising a suitable framework; lateral parallel shafts rotatably aifixed to the said framework; a main drive pulley and secondary drive pulleys affixed to one of the said shafts; a driven pulley fixed, in longitudinal alignment with one of the said secondary drive pulleys, to another of the said shafts and loosely coupled to the said secondary drive pulley by a belt; a vertically operable nigger bar adapted to slidably fit laterally over the last mentioned shaft and longitudinally over a hoisting pulley aflixed to the said shaft; shock absorbing means mounted on the said nigger bar, between the said nigger bar and the said shaft; means connected to the said hoisting pulley and the said nigger bar and adapted to raise the said nigger bar vertically coincidentally with the rotation of the said hoisting pulley; a second driven pulley fixed, in longitudinal alignment with another of the said secondary drive pulleys, to another of the said lateral parallel shafts and loosely coupled to the said secondary drive pulley by a belt; a friction pulley fixed to the last mentioned shaft in longitudinal alignment with the said nigger bar; a friction cable wound on the said friction pulley, such cable attached by one of its ends through a chain to the said nigger bar and by the other of its ends through a tension spring to the said framework; means for tightening said loosely coupled belts singly or in unison, to engage said secondary drive pulleys and driven pulleys, said belt tightening means operated and controlled from a preferred location on the sawmill floor; means for restricting lateral movement of the said nigger bar and guiding the said nigger bar during longitudinal oscillation; shock absorbing means mounted on the last mentioned means.

4.'Means for applying power to a vertically operable nigger bar comprising amain drive pulley and secondary drive pulleys fixed to one of a plurality of parallel shafts, such main drive pulley being coupled to a suitable power source; a driven pulley fixed to another of the said parallel shafts and loosely coupled by a belt to one of the said secondary drive pulleys; a hoisting pulley fixed to the last mentioned shaft, the said nigger bar being adapted to slidably fit over the said hoisting pulley and the last mentioned shaft; means associated with the said hoistin'g pulley and adapted to raise the said nigger bar vertically on rotation of the said hoisting pulley; means for limiting the rotation of the said hoisting pulley during the downward travel of the said nigger bar; another driven pulley affixed to another of the parallel shafts and loosely coupled by a belt to another of the said secondary drive pulleys; a friction pulley fixed to the last mentioned shaft; means associated with the said friction pulley and connected to the said nigger bar adapted to maintain pressure of the said nigger bar against a log positioned on the sawmill carriage; means for tightening the said loosely coupled belts singly or in unison to engage their respective secondary drive pulleys and driven pulleys, such means controlled from a point remote from the said nigger bar; means for restricting lateral movement of the said nigger bar and guiding thesaid nigger bar during longitudinal oscillation.

EMILE GEDEOIN LETOURNEAU.

v REFERENCES CITED The following references are of record in the Weir Oct. 12, 18st 

